Re: Kprobes: pre-handler with interrupts enabled - is it possible?

[Eugene Shatokhin <eugene.shatokhin@rosalab.ru>]

Hi,

I am now working on an example to see if what I suggested earlier is
possible.

During this, I encountered a problem in Kprobes on x86 that prevents
placing them on the insns with %rip-relative addressing.

register_kprobe() returns -EINVAL in such cases because
__copy_instruction() returns 0 (arch/x86/kernel/kprobes/core.c). The
latter is due to the second call to kernel_insn_init() which zeroes the
struct insn instance, including insn.length.

I will send a patch shortly, please consider it for inclusion.

Regards,
Eugene

-- 
Eugene Shatokhin, ROSA
www.rosalab.com